1. Field of the Invention
This invention relates to a slider used in a linear motion rolling guide unit and causing rolling elements to roll on raceway faces provided on a track rail to achieve a smooth relative movement on the rail.
2. Description of the Related Art
Conventionally, this type of slider for a linear motion rolling guide unit is known from JP-2007-100951A.
The slider comprises a casing and end caps secured at the two ends of the casing, and provides for circulation paths which are made up of rolling paths formed in the casing and turning corners formed in the end caps for allowing the rolling elements to move around the circulation paths. The end caps have mounted on them lubricating members impregnated with a lubricant. A portion of each of the lubricating members is exposed to the inside of each of the turning corners formed in the end caps. FIG. 18 shows a specific structure of the lubricating member and the turning corner.
As illustrated in FIG. 18, a turning corner 102 is formed in an end cap 101. The end cap 101 is coupled to a casing which is not shown but located above the end cap 101 in FIG. 18, so that the two ends of the turning corner 102 are each connected directly to a rolling path formed in the casing.
The turning corner 102 is made up of a linear straight portion 102a and arc-shaped portions 102b directly adjoining the straight portion 102a and having a predetermined curvature.
On the other hand, the end cap 101 is fitted with a lubricating member 103. The lubricating member 103 has a raised portion 104 exposed to the straight portion 102a of the turning corner 102. The leading end face of the raised portion 104 has a lubricating face 104a which is parallel to the straight portion 102a. 
A plurality of rolling elements B are installed in the turning corner 102, and roll through the turning corner 102. The rolling elements B make contact with the lubricating face 104a in the process of rolling in the straight portion 102a, and are coated with the lubricant held in the lubricating member 103 and dispensed from the lubricating face 104a. 
In this manner, because the rolling elements B are lubricated during their passage through the turning corner 102, the smooth rolling of the rolling elements B can be maintained for a long time.
In order to lubricate the rolling elements B as described above, it follows that the lubricating face 104a is required to protrude beyond or to be flush with the outer periphery face 105 of the turning corner 102.
However, if the lubricating face 104a projects too much beyond the outer periphery face 105 so as to increase the protrusion x created between the outer periphery face 105 and the lubricating face 104a, this obstructs the smooth rolling of the rolling elements B. On the other hand, if the lubricating face 104a is slightly lower than the outer periphery face 105, the rolling elements B cannot be completely lubricated.
For the purpose of reliably making full use of the lubricating capability without inhibiting the rolling movement of the rolling elements B, it is necessary to ensure accurate dimensions such that the lubricating face 104a and the outer peripheral face 105 are flush with each other. For this purpose, a complicated manufacturing process and intricate assembling process are required, resulting in an increase in manufacturing costs.